[SEL] SEL Digest, Vol 96, Issue 9

[Jerry Evans]

   At 06:00 PM 11/03/12, you wrote:

     Message: 2
     Date: Sat, 10 Mar 2012 14:42:40 -0500
     From: "Lesley K. Spivey" <spiveylk at gru.net>
     Subject: Re: [SEL] SEL Digest, Vol 96, Issue 8
     Lexan is a brand name for polycarbonate, like Chlorox for chlorine
     bleach.  As far as I know auto plastic bumpers, etc. are ABS plastic
     (acrylonitrile butadiene styrene).  It's normally black.  I'm fairly
     sure that there are specialty glues for each of them, solvent type.
     I
     believe ABS glue can be found in plumbing supply places.    Les

   Quite correct Les,
           Lexan is General Electric Plastics's registered Trade name for
   polycarbonate sheet (GE are now known as SABIC Innovative Plastics).
           There are a number of adhesives for polycarbonate usually
   incorporating a solvent which melts the Polycarb. I glue Polycarb very
   successfully for things like showcases with a straight solvent -
   Methylene Chloride. the 2 pieces of PC are placed in contact with each
   other (mating surfaces are important) and then the solvent is injected
   against the join with a syringe needle. Capillary action draws the
   solvent into the joint and the plastic melts together - the joint must
   not be moved for a while and the solvent is allowed to evaporate off
   leaving a beautiful clear bond of pure polycarbonate. There are various
   solvents which work.
           Acrylic (Plexiglas/Perspex)sheets are done the same way but
   with different solvents (I use Chloroform).
           Car bumpers do seem to be mostly made from ABS (but I've come
   across cheap aftermarket versions made from Polypropylene as well).
           ABS is very easy to glue also using solvents (Methyl Ethyl
   Ketone is one) but by far the easiest adhesive to obtain and use on ABS
   is the normal plumbing adhesive used on PVC piping - it works equally
   well on ABS. This contains a solvent to soften the plastic as well as
   certain compatible fillers. ABS (and PVC) are also very easy to paint
   as normal lacquer thinners etches into the surface allowing the paint
   to bond. (ABS is available in any colour you like - not just black.)
           P.S. If anyone on this list lives near Little Rock, Fort Smith
   or Springdale, Arkansas then pop in to a company there called
   Mr.Plastic and ask for Eugene Snyman. I had (and sold in 1986) a
   business in Johannesburg called Mr Plastic and we sold and fabricated
   engineering plastics. Eugene bought the business from me in 1986 and
   sold it a number of years later. He then moved to the USA and started
   again there - using the same logo and name. He will answer any plastic
   related question for you - see:
   <[1]http://mrplastic.us/about-mr-plastic.php>

   Keep the revs up (or down)
   Jerry Evans
   Near Johannesburg in Sunny South Africa.
   Etched Brass Engine Plates made to order:
   <[2]www.oldengine.org/members/evans/plates/index.htm>

References

   1. http://mrplastic.us/about-mr-plastic.php
   2. http://www.oldengine.org/members/evans/plates/index.htm